如何根据 iOS 版本处理推送通知？

Question

对于 iOS7，Parse 在 AppDelegate 中使用以下代码处理推送通知：

[application registerForRemoteNotificationTypes:
 UIRemoteNotificationTypeBadge|
 UIRemoteNotificationTypeAlert|
 UIRemoteNotificationTypeSound];

registerForRemoteNotificationTypes 在 iOS8 中不受支持，而用于在 iOS8 中处理推送通知的新代码现在如下所示：

UIUserNotificationSettings *settings =
[UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert |
 UIUserNotificationTypeBadge |
 UIUserNotificationTypeSound
                                  categories:nil];
[[UIApplication sharedApplication] registerUserNotificationSettings:settings];
[[UIApplication sharedApplication] registerForRemoteNotifications];

在 iOS7 设备上使用这个新代码会导致应用崩溃，因此我需要让代码确定手机的版本，并运行适当的推送通知代码。如何让应用检查这一点并使用正确的？

Answer 1

检查方法的可用性总是比检查操作系统版本更好。

if ([[UIApplication sharedApplication] respondsToSelector:@selector(registerForRemoteNotifications)]) {

    UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert | UIUserNotificationTypeBadge | UIUserNotificationTypeSound categories:nil];

    [[UIApplication sharedApplication] registerUserNotificationSettings:settings];

    [[UIApplication sharedApplication] registerForRemoteNotifications];

} else {

    [[UIApplication sharedApplication] registerForRemoteNotificationTypes:(UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeSound | UIRemoteNotificationTypeAlert)];
}

假设您的部署目标 >= 7.0。

Answer 2

可能是registerForRemoteNotificationTypes: is not supported in iOS 8.0 and later的副本

if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
{
    [[UIApplication sharedApplication] registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:(UIUserNotificationTypeSound | UIUserNotificationTypeAlert | UIUserNotificationTypeBadge) categories:nil]];
    [[UIApplication sharedApplication] registerForRemoteNotifications];
}
else
{
    [[UIApplication sharedApplication] registerForRemoteNotificationTypes:
     (UIUserNotificationTypeBadge | UIUserNotificationTypeSound | UIUserNotificationTypeAlert)];
}